diff --git a/src/network/protocols/server_lobby.cpp b/src/network/protocols/server_lobby.cpp
index 6ab0aa329..14ad97c97 100644
--- a/src/network/protocols/server_lobby.cpp
+++ b/src/network/protocols/server_lobby.cpp
@@ -169,6 +169,7 @@ ServerLobby::~ServerLobby()
 void ServerLobby::initDatabase()
 {
 #ifdef ENABLE_SQLITE3
+    m_last_cleanup_db_time = StkTime::getMonoTimeMs();
     m_db = NULL;
     sqlite3_stmt* stmt = NULL;;
     m_ip_ban_table_exists = false;
@@ -438,7 +439,7 @@ void ServerLobby::initServerStatsTable()
 
     // Update disconnected time (if stk crashed it will not be written)
     query = StringUtils::insertValues(
-        "UPDATE %s SET disconnected_time = datetime('now')"
+        "UPDATE %s SET disconnected_time = datetime('now') "
         "WHERE connected_time = disconnected_time;",
         m_server_stats_table.c_str());
     ret = sqlite3_prepare_v2(m_db, query.c_str(), -1, &stmt, 0);
@@ -781,6 +782,81 @@ void ServerLobby::createServerIdFile()
     }
 }   // createServerIdFile
 
+//-----------------------------------------------------------------------------
+#ifdef ENABLE_SQLITE3
+/* Every 1 minute STK will clean up database:
+ * 1. Set disconnected time to now for non-exists host.
+ */
+void ServerLobby::cleanupDatabase()
+{
+    if (!ServerConfig::m_sql_management || !m_db)
+        return;
+
+    if (StkTime::getMonoTimeMs() < m_last_cleanup_db_time + 60000)
+        return;
+
+    m_last_cleanup_db_time = StkTime::getMonoTimeMs();
+
+    if (m_server_stats_table.empty())
+        return;
+
+    std::string query;
+    auto peers = STKHost::get()->getPeers();
+    std::vector<uint32_t> exist_hosts;
+    if (!peers.empty())
+    {
+        for (auto& peer : peers)
+        {
+            if (!peer->isValidated())
+                continue;
+            exist_hosts.push_back(peer->getHostId());
+        }
+    }
+    if (peers.empty() || exist_hosts.empty())
+    {
+        query = StringUtils::insertValues(
+            "UPDATE %s SET disconnected_time = datetime('now') "
+            "WHERE connected_time = disconnected_time;",
+            m_server_stats_table.c_str());
+    }
+    else
+    {
+        std::ostringstream oss;
+        oss << "UPDATE " << m_server_stats_table
+            << "    SET disconnected_time = datetime('now')"
+            << "    WHERE connected_time = disconnected_time AND"
+            << "    host_id NOT IN (";
+        for (unsigned i = 0; i < exist_hosts.size(); i++)
+        {
+            oss << exist_hosts[i];
+            if (i != (exist_hosts.size() - 1))
+                oss << ",";
+        }
+        oss << ");";
+        query = oss.str();
+    }
+
+    sqlite3_stmt* stmt = NULL;
+    int ret = sqlite3_prepare_v2(m_db, query.c_str(), -1, &stmt, 0);
+    if (ret == SQLITE_OK)
+    {
+        ret = sqlite3_step(stmt);
+        ret = sqlite3_finalize(stmt);
+        if (ret != SQLITE_OK)
+        {
+            Log::error("ServerLobby",
+                "Error finalize database for query %s: %s",
+                query.c_str(), sqlite3_errmsg(m_db));
+        }
+    }
+    else
+    {
+        Log::error("ServerLobby", "Error preparing database for query %s: %s",
+            query.c_str(), sqlite3_errmsg(m_db));
+    }
+}   // cleanupDatabase
+#endif
+
 //-----------------------------------------------------------------------------
 /** Find out the public IP server or poll STK server asynchronously. */
 void ServerLobby::asynchronousUpdate()
@@ -792,6 +868,10 @@ void ServerLobby::asynchronousUpdate()
         m_rs_state.store(RS_NONE);
     }
 
+#ifdef ENABLE_SQLITE3
+    cleanupDatabase();
+#endif
+
     // Check if server owner has left
     updateServerOwner();
 
diff --git a/src/network/protocols/server_lobby.hpp b/src/network/protocols/server_lobby.hpp
index c99c8cd02..e9712e4c1 100644
--- a/src/network/protocols/server_lobby.hpp
+++ b/src/network/protocols/server_lobby.hpp
@@ -79,6 +79,9 @@ private:
 
     bool m_online_id_ban_table_exists;
 
+    uint64_t m_last_cleanup_db_time;
+
+    void cleanupDatabase();
 #endif
     void initDatabase();
 
@@ -131,10 +134,6 @@ private:
     /** Timeout counter for various state. */
     std::atomic<int64_t> m_timeout;
 
-    /** Lock this mutex whenever a client is connect / disconnect or
-     *  starting race. */
-    mutable std::mutex m_connection_mutex;
-
     TransportAddress m_server_address;
 
     std::mutex m_keys_mutex;
@@ -333,8 +332,6 @@ public:
     void finishedLoadingWorld() OVERRIDE;
     ServerState getCurrentState() const { return m_state.load(); }
     void updateBanList();
-    std::unique_lock<std::mutex> acquireConnectionMutex() const
-                   { return std::unique_lock<std::mutex>(m_connection_mutex); }
     bool waitingForPlayers() const;
     virtual bool allPlayersReady() const OVERRIDE
                             { return m_state.load() >= WAIT_FOR_RACE_STARTED; }